Disabling launch_tor timeout when on windows

On windows the python signal module lacks a SIGALRM attribute, breaking launch_tor. Disabling timeouts on windows to avoid this issue - ideally we should find an alternative method for timeing out the function on windows but that can wait. Caught by pythonirc101. Issue is discussed on... https://trac.torproject.org/projects/tor/ticket/5783

Disabling launch_tor timeout when on windows
688f3212 · Damian Johnson · 4d6c8c89 · 688f3212 · 688f3212
Commit 688f3212 authored May 20, 2012 by Damian Johnson
--- a/stem/process.py
+++ b/stem/process.py
@@ -11,6 +11,8 @@ import signal
 import tempfile
 import subprocess

+import stem.util.system
+
 # number of seconds before we time out our attempt to start a tor instance
 DEFAULT_INIT_TIMEOUT = 90

@@ -29,6 +31,9 @@ def launch_tor(tor_cmd = "tor", args = None, torrc_path = None, completion_perce
  while. Usually this is done in 50 seconds or so, but occasionally calls seem
  to get stuck, taking well over the default timeout.
  
+  Our timeout argument does not work on Windows...
+  https://trac.torproject.org/projects/tor/ticket/5783
+  
  Arguments:
    tor_cmd (str)              - command for starting tor
    args (list)                - additional arguments for tor
@@ -48,6 +53,9 @@ def launch_tor(tor_cmd = "tor", args = None, torrc_path = None, completion_perce
    without success
  """
  
+  if stem.util.system.is_windows():
+    timeout = None
+  
  # double check that we have a torrc to work with
  if not torrc_path in (None, NO_TORRC) and not os.path.exists(torrc_path):
    raise OSError("torrc doesn't exist (%s)" % torrc_path)

--- a/stem/util/system.py
+++ b/stem/util/system.py
@@ -44,13 +44,23 @@ GET_CWD_PWDX             = "pwdx %s"
 GET_CWD_LSOF             = "lsof -a -p %s -d cwd -Fn"
 GET_BSD_JAIL_ID_PS       = "ps -p %s -o jid"

+def is_windows():
+  """
+  Checks if we are running on Windows.
+  
+  Returns:
+    bool to indicate if we're on Windows
+  """
+  
+  return platform.system() == "Windows"
+
 def is_bsd():
  """
  Checks if we are within the BSD family of operating systems. This presently
  recognizes Macs, FreeBSD, and OpenBSD but may be expanded later.
  
  Returns:
-    bool to indicate if we're a BSD OS
+    bool to indicate if we're on a BSD OS
  """
  
  return platform.system() in ("Darwin", "FreeBSD", "OpenBSD")
@@ -78,7 +88,7 @@ def is_available(command, cached=True):
    cmd_exists = False
    for path in os.environ["PATH"].split(os.pathsep):
      cmd_path = os.path.join(path, command)
-      if platform.system() == "Windows": cmd_path += ".exe"
+      if is_windows(): cmd_path += ".exe"
      
      if os.path.exists(cmd_path) and os.access(cmd_path, os.X_OK):
        cmd_exists = True